French warning on nuclear reactors being built in China's Guangdong
Weakness found in steel from maker that is also a supplier to Guangdong facilities
France's nuclear safety authority has warned that two nuclear reactors nearing completion in Guangdong could face safety problems after weaknesses were found in steel supplied to a French reactor by the same manufacturer.
The French reactor, at the Flamanville EPR nuclear power plant, is a third-generation pressurised water reactor of similar design and build to the two reactors being installed at a new plant in Taishan. Quality inspectors at Flamanville found an abnormally high concentration of carbon in steel parts capping the reactor vessel's top and bottom during a series of tests carried out by French nuclear company Areva, which is building the reactor.
The excessive carbon would lead to "lower than expected mechanical toughness values", nuclear regulator ASN said in a press statement on its website, without giving more details.
The toughness of the reactor shell was crucial because it relates to the ability of the material to withstand the propagation of cracks. The steel shell of a reactor has to be extremely tough to withstand decades of operation.
It was unknown whether the Taishan reactors had the same problem, but the issue might be worth China's concern, the French authorities said. ASN had "informed" relevant foreign counterparts, the statement said.
"The vessel of a pressurised water reactor is equipment that is particularly important for safety," the ASN added. "It contains the fuel and takes part in the radioactivity second containment barrier."
The problematic steel parts at Flamanville were made by Creusot Forge, a subsidiary of Areva, which also made the same parts for the two reactors in Taishan with similar manufacturing technology, according to a Reuters report. It was unclear whether the Taishan reactors had undergone similar tests before they were shipped to China.